CN107043216A - SiO2Modified low temperature sealing glass and its preparation and application method - Google Patents

Abstract

The invention discloses a low-temperature sealing glass modified by SiO ₂ and its preparation and use method. The molar ratio of ZnO, Na ₂ O, P ₂ O ₅ and SiO ₂ in the raw material composition is 33-45:15-25 : 22~40: 5~25. The present invention introduces SiO ₄ tetrahedron through SiO ₂ , uses its structural similarity to stabilize PO ₄ tetrahedron to strengthen the glass network structure and improve its thermal stability, so that it can still maintain a good glass temperature after soaking in hot water at 80°C for 1000 hours. Stability; and the introduction of SiO ₂ can promote the densification of the glass network structure and reduce the oxygen permeability. The introduction of high concentrations of ZnO and P ₂ O ₅ reduces the transition temperature range of the glass to 380-435°C; the introduction of Na ₂ O can lower the melting temperature of the glass and improve its sealing performance. The glass material obtained in the invention is suitable for LED fluorescent powder sealing, electronic materials and other low-temperature sealing fields.

Description

Low-temperature sealing glass modified by SiO2 and its preparation and application method

technical field

The invention belongs to the technical field of sealing glass preparation, and in particular relates to a _SiO2 -modified low-temperature sealing glass and a preparation and use method thereof.

Background technique

Low-temperature sealing glass (sealing temperature <600°C) is widely used in electronic paste, electric vacuum and microelectronic technology, energy, aerospace, automobile, etc. due to its good heat resistance, chemical stability and high mechanical strength. In many fields, such as in the phosphor sealing of light-emitting diodes (LEDs), whether the performance of the sealing material is good or not directly affects the actual performance of the battery. Sealing glass can also be used for mutual sealing between glass, ceramics, metals, and semiconductors. However, currently domestic and foreign research generally use sealing materials containing Pb, which will pollute the environment. In addition, phosphate glass has gained widespread attention due to its advantages such as low melting temperature, wide adjustable range of expansion coefficient, low price, and can significantly reduce environmental pollution.

The patent application (201310259302.6) discloses a low-temperature lead-free glass powder and its preparation method, but another toxic substance Sb is introduced into the system, which does not solve the environmental protection problem. The patent application (201210366375.0) discloses a lead-free glass material and its preparation method, which avoids environmental pollution through the composition design of P ₂ O ₅ , K ₂ O, Na ₂ O, ZrO ₂ , TiO ₂ and other raw materials, but The softening temperature of the glass ranges from 500 to 600°C, which is difficult to meet the requirements of low-temperature sealing, especially low-temperature and rapid sintering of electronic components. The previous work of our research group discovered that boron-bismuth-zinc system glass can solve the above problems, and applied for a patent. However, because the boron-bismuth-zinc system glass contains the variable valence ion Bi, the color of the glass becomes darker during the sintering process, which makes the light transmittance of the glass in the visible light band lower, and the boron-bismuth-zinc system glass is easy to devitrify. hard to control. Therefore, boron-bismuth-zinc system glasses are relatively limited in terms of optical performance.

Contents of the invention

The object of the present invention is to provide a low-temperature sealing glass modified by SiO ₂ and its preparation and use method. Powder sealing, electronic materials and other low temperature sealing fields.

To achieve the above object, the present invention adopts the following technical solutions:

A low-temperature sealing glass modified by SiO ₂ , the molar ratio of ZnO, Na ₂ O, P ₂ O ₅ , and SiO ₂ in the raw material composition is 33~45:15~25:22~40:5~25; preferably Specifically, the molar ratio of ZnO, Na ₂ O, P ₂ O ₅ , and SiO ₂ is 38~40.5:18~22:27~29.5:10~15.

The preparation method of the SiO modified low _- temperature sealing glass comprises the following steps:

(1) Mix ZnO, Na ₂ O, P ₂ O ₅ , and SiO ₂ uniformly according to the proportion, melt at 880-1100°C and keep warm for 1-4 hours to obtain a glass melt; then quench the obtained glass melt to obtain Glass frit; then crush the glass frit, grind or ball mill, and obtain glass powder after sieving;

(2) Mix the obtained glass powder with binder, dispersant and solvent to form a slurry, ball mill it in a ball mill to disperse it evenly, and after tape casting and natural drying, cut it into the embryo body of the desired shape, That is, the low-temperature sealing glass is produced.

The amount of glass powder, binder, dispersant and solvent in step (2) is calculated by weight percentage: 80-84% of glass powder, 1.5-2% of binder, 0.5-2% of dispersant, 14-17% of solvent %, the sum of its weight percentages is 100%;

Wherein, the binder used is one or more of epoxy resin, methyl cellulose, polyvinyl butyral, and polyvinyl alcohol;

The dispersant used is one or more of fish oil, polyacrylic acid, polyvinyl alcohol, polyacrylamide;

The solvent used is one or more of water, ethanol, isopropanol, n-butanol, toluene, xylene and acetone.

The method of using the _SiO2 -modified low-temperature sealing glass is to place the low-temperature sealing glass on the part to be sealed, raise the temperature to 400-500°C at a rate of 1-5°C/min in an electric furnace, and keep the temperature 0.5-1h, then raise the temperature to 500-650°C at a rate of 1-5°C/min, heat preservation for 0.5-1h, and the sealing is completed.

Significant advantage of the present invention is:

(1) The present invention introduces SiO ₄ tetrahedra through SiO ₂ to strengthen the glass network structure, thereby improving its thermal stability and reducing the tendency of crystallization, so that the obtained glass material can still maintain good crystallization after soaking in hot water at 80°C for 1000 hours. Stability; at the same time, the introduction of _SiO2 can promote the densification of the glass network structure and reduce the oxygen permeability;

(2) The present invention introduces high-concentration ZnO and P ₂ O ₅ , and through the coordination of the two, the transition temperature range of the glass is reduced to 380-435°C;

(3) The introduction of Na ₂ O in the present invention can reduce the melting temperature of glass and improve its sealing performance;

(4) The preparation raw materials of the present invention are simple and easy to obtain, the process is stable, and the conditions for practical and industrialization are met.

Description of drawings

Fig. 1 is the thermal expansion curve of the low-temperature sealing glass obtained in Examples 1-4 under parallel experimental conditions.

Fig. 2 is the DSC curve of the low-temperature sealing glass obtained in Examples 1-4 under parallel experimental conditions.

detailed description

A low-temperature sealing glass modified by SiO ₂ , the molar ratio of ZnO, Na ₂ O, P ₂ O ₅ , and SiO ₂ in the raw material composition is 33~45:15~25:22~40:5~25; preferably Specifically, the molar ratio of ZnO, Na ₂ O, P ₂ O ₅ , and SiO ₂ is 38~40.5:18~22:27~29.5:10~15.

The preparation method of the SiO modified low _- temperature sealing glass comprises the following steps:

(1) Mix ZnO, Na ₂ O, P ₂ O ₅ , and SiO ₂ uniformly according to the proportion, melt at 880-1100°C and keep warm for 1-4 hours to obtain a glass melt; then quench the obtained glass melt to obtain Glass frit; then crush the glass frit, grind or ball mill, and obtain glass powder after sieving;

(2) Mix the obtained glass powder with binder, dispersant and solvent to form a slurry, ball mill it in a ball mill to disperse it evenly, and after tape casting and natural drying, cut it into the embryo body of the desired shape, That is, the low-temperature sealing glass is produced.

The amount of glass powder, binder, dispersant and solvent in step (2) is calculated by weight percentage: 80-84% of glass powder, 1.5-2% of binder, 0.5-2% of dispersant, 14-17% of solvent %, the sum of its weight percentages is 100%;

Wherein, the binder used is one or more of epoxy resin, methyl cellulose, polyvinyl butyral, and polyvinyl alcohol;

The dispersant used is one or more of fish oil, polyacrylic acid, polyvinyl alcohol, polyacrylamide;

The solvent used is one or more of water, ethanol, isopropanol, n-butanol, toluene, xylene and acetone.

The method of using the _SiO2 -modified low-temperature sealing glass is to place the low-temperature sealing glass on the part to be sealed, raise the temperature to 400-500°C at a rate of 1-5°C/min in an electric furnace, and keep the temperature 0.5-1h, then raise the temperature to 500-650°C at a rate of 1-5°C/min, heat preservation for 0.5-1h, and the sealing is completed.

In order to make the content of the present invention easier to understand, the technical solutions of the present invention will be further described below in conjunction with specific embodiments, but the present invention is not limited thereto.

Table 1 Component distribution ratio of low-temperature sealing glass in Examples 1-4 (mol percent, %)

Example 1:

Weigh a certain amount of analytically pure raw materials (ZnO, Na ₂ O, P ₂ O ₅ , SiO ₂ ) according to the ratio of Example 1 in Table 1, and use a planetary ball mill for 24 hours to mix them evenly; then put the powder Put it into a platinum crucible, put it in a box-type resistance furnace, heat it to 900°C at 3°C/min in an air atmosphere, and keep it warm for 1h to obtain a glass melt; then take out the crucible, pour the obtained glass melt into deionized water to quench, The glass frit is obtained by drying; the obtained glass frit is ground and passed through a 100-mesh sieve to obtain glass powder. The obtained glass powder is mixed with polyvinyl alcohol, fish oil, ethanol and toluene in a weight ratio of 80:2:1:10:7 to form a slurry, which is ball-milled in a ball mill to disperse it evenly, and then cut into The embryo body of the desired shape is the low-temperature sealing glass. This example is a preferred composition.

Place the obtained low-temperature sealing glass on the part to be sealed, raise the temperature in an electric furnace to 400°C at a rate of 2°C/min, and keep it warm for 1h, then raise the temperature at a rate of 2°C/min to 500°C, and keep it warm for 1h, that is Complete the seal.

Pour the heat-preserved glass melt into a preheated stainless steel abrasive tool to obtain a glass cylinder with Φ=10mm and d=25mm, and test it on a NETZSCH DIL 402EP thermal dilatometer at a heating rate of 10°C/min to obtain the glass transition Point and softening point, the results are shown in Figures 1 and 2. Figures 1 and 2 show that the glass transition point of the sealing glass with 5% SiO ₂ added is 388°C, the softening point is 394°C, and the coefficient of linear expansion is 1.41×10 ^-5 /K.

The obtained low-temperature sealing glass has a weight loss rate of less than 0.001% after being placed in hot water at 80°C for 1000 hours. The oxygen permeability measured under the oxygen permeability test condition is 1cm ³ /m ² ·d.

Example 2:

Weigh a certain amount of analytically pure raw materials (ZnO, Na ₂ O, P ₂ O ₅ , SiO ₂ ) according to the ratio of Example 2 in Table 1, and use a planetary ball mill for 24 hours to mix them evenly; then put the powder Put it into a platinum crucible, place it in a box-type resistance furnace, heat it to 950°C at 3°C/min in an air atmosphere, and keep it warm for 1h to obtain a glass melt; then take out the crucible, pour the obtained glass melt into deionized water to quench, The glass frit is obtained by drying; the obtained glass frit is ground and passed through a 100-mesh sieve to obtain glass powder. The obtained glass powder is mixed with methyl cellulose, polyvinyl alcohol, n-butanol and acetone in a weight ratio of 82:2:2:8:6 to form a slurry, which is ball milled in a ball mill to disperse it evenly. After drying, the embryo body is cut into the desired shape, and the low-temperature sealing glass is obtained. This example is a preferred composition.

Place the obtained low-temperature sealing glass on the part to be sealed, raise the temperature in an electric furnace to 400°C at a rate of 2°C/min, and keep it warm for 1h, then raise the temperature at a rate of 2°C/min to 500°C, and keep it warm for 1h, that is Complete the seal.

Pour the heat-preserved glass melt into a preheated stainless steel abrasive tool to obtain a glass cylinder with Φ=10mm and d=25mm, and test it on a NETZSCH DIL 402EP thermal dilatometer at a heating rate of 10°C/min to obtain the glass transition Point and softening point, the results are shown in Figures 1 and 2. Figures 1 and 2 show that the glass transition point of the sealing glass with 10% SiO ₂ added is 409°C, the softening point is 415°C, and the coefficient of linear expansion is 1.39×10 ^-5 /K.

The obtained low-temperature sealing glass has a weight loss rate of less than 0.001% after being placed in hot water at 80°C for 1000 hours. The oxygen permeability measured under the oxygen permeability test condition is 0.1cm ³ /m ² ·d.

Example 3:

Weigh a certain amount of analytically pure raw materials (ZnO, Na ₂ O, P ₂ O ₅ , SiO ₂ ) according to the ratio of Example 3 in Table 1, and use a planetary ball mill for 24 hours to mix them evenly; then put the powder Put it into a platinum crucible, put it in a box-type resistance furnace, heat it to 1000°C at 3°C/min in an air atmosphere, and keep it warm for 1h to obtain a glass melt; then take out the crucible, pour the obtained glass melt into deionized water to quench, The glass frit is obtained by drying; the obtained glass frit is ground and passed through a 100-mesh sieve to obtain glass powder. Mix the obtained glass powder with epoxy resin, polyacrylamide, isopropanol and toluene in a weight ratio of 84:1.5:0.5:9:5 to form a slurry, mill it in a ball mill to disperse it evenly, cast it, and dry it naturally Finally, the embryo body is cut into the required shape, and the low-temperature sealing glass is obtained. This example is a preferred composition.

Place the obtained low-temperature sealing glass on the part to be sealed, raise the temperature in an electric furnace to 450°C at a rate of 2°C/min, and keep it warm for 1h, then raise the temperature at a rate of 2°C/min to 550°C, and keep it warm for 1h, that is Complete the seal.

Pour the heat-preserved glass melt into a preheated stainless steel abrasive tool to obtain a glass cylinder with Φ=10mm and d=25mm, and test it on a NETZSCH DIL 402EP thermal dilatometer at a heating rate of 10°C/min to obtain the glass transition Point and softening point, the results are shown in Figures 1 and 2. Figures 1 and 2 show that the glass transition point of the sealing glass with 15% SiO ₂ added is 419°C, the softening point is 427°C, and the coefficient of linear expansion is 1.35×10 ^-5 /K.

The obtained low-temperature sealing glass has a weight loss rate of less than 0.001% after being placed in hot water at 80°C for 1000 hours. The oxygen permeability measured under the oxygen permeability test condition is 0.05cm ³ /m ² ·d.

Example 4:

Weigh a certain amount of analytically pure raw materials (ZnO, Na ₂ O, P ₂ O ₅ , SiO ₂ ) according to the ratio of Example 4 in Table 1, and use a planetary ball mill for 24 hours to mix them evenly; then put the powder Put it into a platinum crucible, put it in a box-type resistance furnace, heat it to 1050°C at 3°C/min in an air atmosphere, and keep it warm for 1h to obtain a glass melt; then take out the crucible, pour the obtained glass melt into deionized water to quench, The glass frit is obtained by drying; the obtained glass frit is ground and passed through a 100-mesh sieve to obtain glass powder. The obtained glass powder is mixed with polyvinyl butyral, polyacrylic acid, isopropanol and acetone at a weight ratio of 83:2:1:9:5 to form a slurry, which is ball-milled in a ball mill to disperse it evenly, and cast, After natural drying, the embryo body is cut into the required shape, and the low-temperature sealing glass is obtained. This example is a preferred composition.

Place the obtained low-temperature sealing glass on the part to be sealed, raise the temperature in an electric furnace to 450°C at a rate of 2°C/min, and keep it warm for 1h, then raise the temperature at a rate of 2°C/min to 550°C, and keep it warm for 1h, that is Complete the seal.

Pour the heat-preserved glass melt into a preheated stainless steel abrasive tool to obtain a glass cylinder with Φ=10mm and d=25mm, and test it on a NETZSCH DIL 402EP thermal dilatometer at a heating rate of 10°C/min to obtain the glass transition Point and softening point, the results are shown in Figures 1 and 2. Figures 1 and 2 show that the glass transition point of the sealing glass with 20% SiO ₂ added is 432°C, the softening temperature is 448°C, and the coefficient of linear expansion is 1.32×10 ^-5 /K.

The obtained low-temperature sealing glass has a weight loss rate of about 0.001% after being placed in hot water at 80°C for 1000 hours. The oxygen permeability measured under the oxygen permeability test condition is 0.05 cm ³ /m ² ·d.

The present invention obtains SiO ₂ modified sealing glass that can be sealed at low temperature through the above embodiments. Its remarkable effect is concentrated in that it has good stability and excellent airtightness in the use environment, and is suitable for LED phosphor sealing, electronic materials and other low-temperature sealing fields.

The above descriptions are only preferred embodiments of the present invention, and all equivalent changes and modifications made according to the scope of the patent application of the present invention shall fall within the scope of the present invention.

Claims (7)

1. A low-temperature sealing glass modified by SiO ₂ , characterized in that the molar ratio of ZnO, Na ₂ O, P ₂ O ₅ , and SiO ₂ in the raw material composition is 33~45:15~25:22~40: 5~25. 2. The SiO ₂ modified low-temperature sealing glass according to claim 1, characterized in that the molar ratio of ZnO, Na ₂ O, P ₂ O ₅ , and SiO ₂ is 38~40.5:18~22:27~ 29.5: 10~15. 3. A method of preparing _SiO2 modified low-temperature sealing glass as claimed in claim 1, characterized in that: comprising the following steps: (1) Mix ZnO, Na ₂ O, P ₂ O ₅ , and SiO ₂ uniformly according to the proportion, melt at 880-1100°C and keep warm for 1-4 hours to obtain a glass melt; then quench the obtained glass melt to obtain Glass frit; then crush the glass frit, grind or ball mill, and obtain glass powder after sieving; (2) Mix the obtained glass powder with binder, dispersant and solvent to form a slurry, ball mill to make it uniformly dispersed, and after tape casting and natural drying, cut it into the embryo body of the desired shape, that is, The low temperature sealing glass. 4. The method for preparing _SiO2 -modified low-temperature sealing glass according to claim 3, characterized in that: the binder used in step (2) is epoxy resin, methyl cellulose, polyvinyl butyral Aldehyde, one or more of polyvinyl alcohol. 5. The method for preparing _SiO2 -modified low-temperature sealing glass according to claim 3, characterized in that: the dispersant used in step (2) is one of fish oil, polyacrylic acid, polyvinyl alcohol, and polyacrylamide species or several. 6. The method for preparing _SiO2 -modified low-temperature sealing glass according to claim 3, characterized in that: the solvent used in step (2) is water, ethanol, isopropanol, n-butanol, toluene, xylene , one or more of acetone. 7. A method of using _SiO2 modified low-temperature sealing glass as claimed in claim 1, characterized in that: the low-temperature sealing glass is placed on the part to be sealed, and heated in an electric furnace at 1-5°C Heat up to 400-500°C at a rate of 1-5°C/min, hold for 0.5-1h, then heat up to 500-650°C at a rate of 1-5°C/min, hold for 0.5-1h to complete the sealing.